The following code shows how to mark arrow left icon.
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css"
href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap-combined.min.css">
<script type='text/javascript'
src="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/js/bootstrap.min.js"></script>
<!-- www . j a v a 2 s .co m-->
</head>
<body style='margin:30px'>
<div class="cb_inline_block">
<div>
<a class="btn right-margin" href="/"><i class="icon-arrow-left"></i></a>
</div>
</div>
</body>
</html>